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Annual International Conference of the... Nov 2021Camera systems have been studied as a means for ubiquitous remote photoplethysmography. It was first considered for daytime applications using ambient light. However,...
Camera systems have been studied as a means for ubiquitous remote photoplethysmography. It was first considered for daytime applications using ambient light. However, main applications for continuous monitoring are in dark or low-light conditions (e.g. sleep monitoring) and, more recently, suitable light sources and simple camera adaptations have been considered for infrared-based solutions. This paper explores suitable camera configurations for pulse-rate monitoring during both day and night (24/7). Various configurations differing in the recorded spectral range are defined, i.e. straight-forward adaptations of a standard RGB camera by choosing proper optical filters. These systems have been studied in a benchmark involving day and night monitoring with various degrees of motion disturbances. The results indicate that, for the 24/7 monitoring, it is best to deploy the full spectral band of an RGB camera, and this can be done without compromising the monitoring performance at night.
Topics: Heart Rate; Humans; Monitoring, Physiologic; Photoplethysmography; Pulse; Sleep
PubMed: 34891624
DOI: 10.1109/EMBC46164.2021.9630497 -
Annual International Conference of the... Jul 2020Photoplethysmography (PPG) is a non-invasive, low-cost optical technique used to assess the cardiovascular system. In recent years, PPG-based heart rate measurement has...
Photoplethysmography (PPG) is a non-invasive, low-cost optical technique used to assess the cardiovascular system. In recent years, PPG-based heart rate measurement has gained significant attention due to its popularity in wearable devices, as well as its practicality relative to electrocardiography (ECG). Studies comparing the dynamics of ECG- and PPG-based heart rate measures have found small differences between these two modalities; differences related to the physiological processes behind each technique. In this work, we analyzed the spectral coherence and the signal-to-noise ratio between isolated PPG pulses and the raw PPG signal in order to: (i) determine the optimal filter to enhance pulse detection from raw PPG for improved heart rate estimation, and (ii) characterize the spectral content of the PPG pulse. The proposed methods were evaluated on 27000 pulses from a PPG database acquired from 42 participants (adults and children). The results showed that the optimal bandpass filter to enhance PPG from the adult group was 0.6-3.3 Hz, while for the children group it was 1.0-2.7 Hz. The spectral analysis on the pulse signal showed that similar bandwidths were found for the adult (0.8-2.4 Hz) and children (0.9-2.7 Hz) groups. We hope that the results presented herein serve as a baseline for pulse detection algorithms and assist with the development of more sophisticated PPG processing algorithms.
Topics: Adult; Algorithms; Child; Electrocardiography; Heart Rate; Humans; Photoplethysmography; Signal Processing, Computer-Assisted
PubMed: 33018133
DOI: 10.1109/EMBC44109.2020.9175396 -
Applied Psychophysiology and Biofeedback Jun 2024Slow paced breathing has been demonstrated to provide significant health benefits for a person's health, and, during breathing sessions, it is desirable to monitor that...
Slow paced breathing has been demonstrated to provide significant health benefits for a person's health, and, during breathing sessions, it is desirable to monitor that a person is actually compliant with the breath pacer. We explore the potential use of pulse rate variability to monitor compliance with a breath pacer during meditation sessions. The study involved 6 human subjects each participating in 2-3 trials, where they are asked to follow or not to follow the breath pacer, where we collected data on how the magnitude of pulse rate variability changed. Two methods, logistic regression and a running standard deviation technique, were developed to detect non-compliance with the breath pacer based on pulse rate variability metrics. Results indicate that using pulse rate variability alone may not reliably detect non-compliance with the breath pacer. Both models exhibited limitations in terms of false positives and false negatives, with accuracy ranging from 67 to 65%. Existing methods involving visual, audio, and motion signals currently perform better for monitoring compliance with the breath pacer.
Topics: Humans; Heart Rate; Male; Female; Adult; Patient Compliance; Monitoring, Physiologic; Meditation; Respiration
PubMed: 38214800
DOI: 10.1007/s10484-023-09617-y -
BMC Infectious Diseases Oct 2023Pneumonia is the leading infectious cause of mortality worldwide and one of the most common lower respiratory tract infections that is contributing significantly to the...
BACKGROUND
Pneumonia is the leading infectious cause of mortality worldwide and one of the most common lower respiratory tract infections that is contributing significantly to the burden of antibiotic consumption. The study aims to identify the determinants of the progress of pulse rate, body temperature and time to recovery of pneumonia patients.
METHOD
A prospective cohort study design was used from Felege Hiwot referral hospital on 214 sampled pneumonia patients from March 01, 2022 up to May 31, 2022. The Kaplan-Meier survival estimate and Log-Rank test was used to compare the survival time. Joint model of bivariate longitudinal and time to event model was used to identify factors of longitudinal change of pulse rate and body temperature with time to recovery jointly.
RESULT
As the follow up time of pneumonia patient's increase by one hour the average longitudinal change of pulse rate and body temperature were decreased by 0.4236 bpm and 0.0119 [Formula: see text]. The average longitudinal change of pulse rate and body temperature of patients who lived in rural was 1.4602 bpm and 0.1550 [Formula: see text] times less as compared to urban residence. Patients who had dangerous signs are significantly increased the average longitudinal change of pulse rate and body temperature by 2.042 bpm and 0.6031 [Formula: see text] as compared to patients who had no dangerous signs. A patient from rural residence was 1.1336 times more likely to experience the event of recovery as compared to urban residence. The estimated values of the association parameter for pulse rate and body temperature were -0.4236 bpm and -0.0119 respectively, which means pulse rate and body temperature were negatively related with patients recovery time.
CONCLUSION
Pulse rate and body temperature significantly affect the time to the first recovery of pneumonia patients who are receiving treatment. Age, residence, danger sign, comorbidity, baseline symptom and visiting time were the joint determinant factors for the longitudinal change of pulse rate, body temperature and time to recovery of pneumonia patients. The joint model approach provides precise dynamic predictions, widespread information about the disease transitions, and better knowledge of disease etiology.
Topics: Humans; Body Temperature; Heart Rate; Prospective Studies; Pneumonia; Patients
PubMed: 37828463
DOI: 10.1186/s12879-023-08646-6 -
Blood Pressure Monitoring Dec 2020Ambulatory blood pressure monitoring (ABPM) on the oscillometric method is applicable in patients with atrial fibrillation, but the mean pulse rate is or not similar to...
Does the mean 24-h pulse rate from ambulatory blood pressure monitoring reflect the mean 24-h ventricular rate from Holter electrocardiogram in atrial fibrillation patients?
BACKGROUND
Ambulatory blood pressure monitoring (ABPM) on the oscillometric method is applicable in patients with atrial fibrillation, but the mean pulse rate is or not similar to the ventricular rate from the Holter in atrial fibrillation patients remains unknown.
METHODS
This study included 228 persistent atrial fibrillation patients who received simultaneous 24-h ABPM and 24-h Holter. The mean 24-h pulse rate and the mean 24-h ventricular rate were calculated, and mVR-mPR was used to reflect the difference between them. The SD of 24-h pulse rate values was calculated as SD-pulse rate. Furthermore, according to the SD-pulse rate, the patients were divided into ≤5, 6-10, 11-15 and >15 bpm subgroups.
RESULTS
For the total population, the mean 24-h pulse rate is positively correlated with the mean 24-h ventricular rate, and the Bland-Altman plot showed quite wide 95% limits. As the SD-pulse rate increased, the 24-h mVR-mPR also increased. The mean 24-h mVR-mPR was 0.5 bpm when SD-pulse rate ≤5, 3.5 bpm when SD-pulse rate of 6-10, 7.6 bpm when SD-pulse rate of 11-15, and 12.5 bpm when SD-pulse rate >15 bpm, respectively. Meanwhile, in the SD-pulse rate 0-10 subgroup, the 95% limits were only from -13.8 to 19.7 bpm, while in the >10 subgroup, these values were from -19.5 to 36.5 bpm.
CONCLUSION
The mean 24-h pulse rate should not be used to represent the true ventricular rate for all atrial fibrillation patients. However, when lower the SD-pulse rate, the mVR-mPR becomes smaller.
Topics: Atrial Fibrillation; Blood Pressure Monitoring, Ambulatory; Electrocardiography; Electrocardiography, Ambulatory; Heart Rate; Heart Ventricles; Humans
PubMed: 32815920
DOI: 10.1097/MBP.0000000000000481 -
IEEE Transactions on Bio-medical... Oct 2013Remote photoplethysmography (rPPG) enables contactless monitoring of the blood volume pulse using a regular camera. Recent research focused on improved motion...
Remote photoplethysmography (rPPG) enables contactless monitoring of the blood volume pulse using a regular camera. Recent research focused on improved motion robustness, but the proposed blind source separation techniques (BSS) in RGB color space show limited success. We present an analysis of the motion problem, from which far superior chrominance-based methods emerge. For a population of 117 stationary subjects, we show our methods to perform in 92% good agreement ( ±1.96σ) with contact PPG, with RMSE and standard deviation both a factor of 2 better than BSS-based methods. In a fitness setting using a simple spectral peak detector, the obtained pulse-rate for modest motion (bike) improves from 79% to 98% correct, and for vigorous motion (stepping) from less than 11% to more than 48% correct. We expect the greatly improved robustness to considerably widen the application scope of the technology.
Topics: Algorithms; Blood Flow Velocity; Colorimetry; Diagnosis, Computer-Assisted; Heart Rate; Humans; Photography; Photoplethysmography; Reproducibility of Results; Sensitivity and Specificity; Skin Physiological Phenomena
PubMed: 23744659
DOI: 10.1109/TBME.2013.2266196 -
Sensors (Basel, Switzerland) Mar 2024Wearable technology and neuroimaging equipment using photoplethysmography (PPG) have become increasingly popularized in recent years. Several investigations deriving...
Wearable technology and neuroimaging equipment using photoplethysmography (PPG) have become increasingly popularized in recent years. Several investigations deriving pulse rate variability (PRV) from PPG have demonstrated that a slight bias exists compared to concurrent heart rate variability (HRV) estimates. PPG devices commonly sample at ~20-100 Hz, where the minimum sampling frequency to derive valid PRV metrics is unknown. Further, due to different autonomic innervation, it is unknown if PRV metrics are harmonious between the cerebral and peripheral vasculature. Cardiac activity via electrocardiography (ECG) and PPG were obtained concurrently in 54 participants (29 females) in an upright orthostatic position. PPG data were collected at three anatomical locations: left third phalanx, middle cerebral artery, and posterior cerebral artery using a Finapres NOVA device and transcranial Doppler ultrasound. Data were sampled for five minutes at 1000 Hz and downsampled to frequencies ranging from 20 to 500 Hz. HRV (via ECG) and PRV (via PPG) were quantified and compared at 1000 Hz using Bland-Altman plots and coefficient of variation (CoV). A sampling frequency of ~100-200 Hz was required to produce PRV metrics with a bias of less than 2%, while a sampling rate of ~40-50 Hz elicited a bias smaller than 20%. At 1000 Hz, time- and frequency-domain PRV measures were slightly elevated compared to those derived from HRV (mean bias: ~1-8%). In conjunction with previous reports, PRV and HRV were not surrogate biomarkers due to the different nature of the collected waveforms. Nevertheless, PRV estimates displayed greater validity at a lower sampling rate compared to HRV estimates.
Topics: Female; Humans; Heart Rate; Autonomic Nervous System; Benchmarking; Correlation of Data; Electrocardiography
PubMed: 38610260
DOI: 10.3390/s24072048 -
Journal of Dairy Science Jul 2018Pulse oximetry is a well-established technique in human and veterinary medicine. In farm animals, it could also be a useful tool for the detection of critical conditions...
Pulse oximetry is a well-established technique in human and veterinary medicine. In farm animals, it could also be a useful tool for the detection of critical conditions relating to oxygen supply and the cardiovascular system. Among other uses, an innovative application could be the monitoring of fetuses during birth. This could help in the early identification of critical situations and support farmers and veterinarians in their decision to start obstetric or life-support interventions. Until now, however, its use in ruminant medicine was still limited to experimental applications. The objective of this study was to evaluate the accuracy of the Radius-7 Wearable Pulse CO-Oximeter (Masimo Corporation, Irvine, CA) for monitoring vital parameters in newborn calves. All measurements were conducted on animals in the lying down position. The sensor of the pulse oximeter was placed in the interdigital space of the calves' front legs and fixed with a homemade latex hoof cover. The pulsoximetric measurements of arterial oxygen saturation (SpO) in 40 newborn calves were compared with the corresponding results (SaO) from a portable blood gas analyzer (VetScan iStat1, Abaxis Inc., Union City, CA), which served as the reference. For this, an arterial blood sample was taken from the medial intermediate branch of the caudal auricular artery. In addition, the pulse rate was measured in 10 calves aged between 0 and 7 d with the pulse oximeter and simultaneously with a heart rate belt (Polar Equine Belt, Polar Electro Oy, Kempele, Finland) to determine their level of agreement. Spearman correlation coefficient for oxygen saturation was 93.8% for the pulse oximeter and the blood gas analyzer, and 97.7% for the pulse rate measured with the pulse oximeter and the heart rate belt. Bland-Altman plots revealed an overestimation of SaO by 2.95 ± 6.39% and an underestimation of the pulse rate by -0.41 ± 3.18 beats per minute compared with the corresponding reference methods. In summary, the pulse oximeter is suitable for continuous monitoring of arterial oxygen saturation and pulse in newborn Holstein Friesian calves. For practical use, purpose-built technical equipment is required to attach the sensor to the calves' legs.
Topics: Animals; Blood Gas Analysis; Cattle; Heart Rate; Humans; Oximetry; Oxygen
PubMed: 29705429
DOI: 10.3168/jds.2017-14266 -
Methods of Information in Medicine May 2016Heart rate variability (HRV) is a signal obtained from RR intervals of electrocardiography (ECG) signals to evaluate the balance between the sympathetic nervous system...
BACKGROUND
Heart rate variability (HRV) is a signal obtained from RR intervals of electrocardiography (ECG) signals to evaluate the balance between the sympathetic nervous system and the parasympathetic nervous system; not only HRV but also pulse rate variability (PRV) extracted from finger pulse plethysmography (PPG) can reflect irregularities that may occur in heart rate and control procedures.
OBJECTIVES
The purpose of this study is to compare the HRV and PRV during hypoglycemia in order to evaluate the features that computed from PRV that can be used in detection of hypoglycemia.
METHODS
To this end, PRV and HRV of 10 patients who required testing with insulin-induced hypoglycemia (IIHT) in Clinics of Endocrinology and Metabolism Diseases of Bezm-i Alem University (Istanbul, Turkey), were obtained. The recordings were done at three stages: prior to IIHT, during the IIHT, and after the IIHT. We used Bland-Altman analysis for comparing the parameters and to evaluate the correlation between HRV and PRV if exists.
RESULTS
Significant correlation (r > 0.90, p < 0.05) and close agreement were found between HRV and PRV for mean intervals, the root-mean square of the difference of successive intervals, standard deviation of successive intervals and the ratio of the low-to-high frequency power.
CONCLUSIONS
In conclusion, all the features computed from PRV and HRV have close agreement and correlation according to Bland-Altman analyses' results and features computed from PRV can be used in detection of hypoglycemia.
Topics: Algorithms; Female; Heart Rate; Humans; Hypoglycemia; Insulin; Male; Middle Aged; Pulse; Signal Processing, Computer-Assisted
PubMed: 27063926
DOI: 10.3414/ME15-01-0088 -
Journal of the American Geriatrics... Dec 2022
Topics: Humans; Heart Rate; Polysomnography; Sleep Apnea, Obstructive
PubMed: 36111674
DOI: 10.1111/jgs.18040